It has been common practice for sometime in the truck rental industry to supply a ramp with the truck to facilitate loading and unloading the truck. A significant advance was made in this art when inventors recognized the possibility of providing a storage space for the ramp between the longitudinal frame members of the truck chassis.
Storage of the ramp in the frame of the truck offers several advantages. Such storage is outside the body of the truck and therefore does not occupy valuable cargo space nor interfere with articles stored in the truck body. Secondly, this storage arrangement does not increase the height of the truck as some prior storage arrangements did. And, further, this storage arrangement positions the ramp at the rear of the truck immediately beneath the floor of the truck body where it is accessible to the user who merely needs to withdraw the ramp from its storage space and place it in use.
Representative prior art arrangements for frame storage of ramps are disclosed in a series of three United States patents granted to John C. Abromavage and Henry S. Shattles, namely: U.S. Pat. No. 3,511,393, granted May 12, 1970 for "RAMP ASSEMBLY"; U.S. Pat. No. 3,559,826, granted Feb. 2, 1971 for "AUTOMOTIVE CHASSIS"; and U.S. Pat. No. 3,713,662, granted Jan. 30, 1973 for "CHASSIS WITH STORAGE SPACE".
The principal shortcoming of the storage arrangements of the Abromavage et al patents lies in the design of the transverse members employed to connect the longitudinal frame members. The transverse frame members of these patents, although designed to accommodate a ramp, have substantial structure within the space between the longitudinal frame members which significantly limits the size of the ramp that can be stored.
Ramp width is of considerable importance because the wider the ramp the more easily it can be navigated by persons loading and unloading the truck. And depth is also important because a thicker ramp can be a stronger ramp.
There continues to be a need, therefore, for a ramp storage arrangement in the frame of a truck that will maximize the size of the ramp which can be stored therein.